The projected activities of the Rheumatic Diseases Core Center continues to concentrate on the development of basic information regarding the inflammatory processes so as to explore pathological mechanisms and to develop and evaluate better forms of treatment in patients with rheumatic and related diseases. To accomplish the specific aims, the Center has 6 Cores: an Inpatient/Outpatient facility to clinically evaluate and provide patients; a Cytofluorograph Core to provide for analysis of cell surface markers and cell sorting capability; a Molecular Biology Core to provide oligonucleotide probes; a Morphology Core for enhanced characterization of cellular event; a Laboratory Core for specific projects; and an Administrative Core. Specific studies include (1) determining whether samples of tissue DNA from patients with any Connective tissue disease contain sequences homologous to retroviral sequences; (2) the status of CRl receptor synthesis and metabolism in neutrophils in patients with RA and SLE; (3) identity RFLP's in CR1 associated with low erythrocyte CRl receptor levels; (4) the functional properties, RFLP, and mRNA of B cell CR2 receptors in patients with RA and SLE; (5) a molecular analysis of a cell alpha, beta, gamma and delta chains, IL-2R, and Ia receptors in peripheral blood and synovial tissue in patients with rheumatic diseases; (6) a molecular analysis of cytokine and T cell receptor mRNA in peripheral blood and synovial cells of patients with RA; (7) the role of mast cells in fibroblast proliferation, chondrocyte activation and graft vs host disease (8) the regulation of the lipoxygenase pathway in normodense and hypodense eosinophiles in hypereosinophilic syndromes; (9) the definition of IL-1 inhibitors in RA joint fluid and SLE hyperglobulinemia; (10) assessment of the relationship between renal function and kallikrein excretion in patients with Sjogren's; (11) analysis of the opsonic and immunochemical properties of synovial fluid fibornectin fragments; (12) definition of genes associated/linked to SLE; (13) definition of genes involved in the immunoregulation of ANA; (14) definition of the genes associated with in polymyositis; (15) determination of the clinical efficacy of dietary fish oil in rheumatoid and psoriatic arthritis and on arachidonic metabolism; (16) a randomized clinical trial to assess the efficacy of radiation synovectomy in patients with RA; (17) development of an immunotoxin to specifically abrogate anti-DNA production; and (18) development of a clinically useful, reproducible activity index in patients with SLE.